Ultrasonic transducer coupler for flaw detection systems

Claim 1

In an inspection device, especially for tubular test pieces, an ultrasonic transducer coupler comprising: (a) a housing having a cavity for a water couplant, said cavity having an inlet adapted for introducing a liquid couplant, the housing having a bottom and said inlet communicating with the cavity through the bottom of the housing, the inlet opening into the cavity adjacent a side wall of the cavity in a direction to introduce the liquid couplant in a swirling motion at the bottom of the cavity along a path tangential to said wall thereof, the cavity having a high point formed with an air vent, whereby to fill the cavity with said couplant while simultaneously exhausting air through the outlet; (b) a transducer holder mounted in the housing within the cavity; (c) a transucer carried by the holder and having a lens through which an ultrasonic beam is directed through the cavity from the transducer; (d) means carried by the housing for effecting precision adjustments of the transducer holder; (e) a face plate having a face contoured to complement the contour of the test piece being inspected with a narrow gap being left therebetween, said face plate having an opening in communication with the cavity, the opening being coincident with the path along which the beam from the transducer is propagated for passage of the beam through the opening against a test piece that is being inspected, the inlet for the liquid couplant opening into the cavity substantially normally to the path along which the transducer beam is propagated whereby the couplant will be introduced in a path swirling about the path of the beam; and (f) means for shutting off the air outlet to the further exhaustion of air therethrough when the cavity is completely filled, whereby upon filling of the cavity with the couplant the outflow of air will be terminated, with further flow of the couplant into the cavity being at a rate sufficient to replace, on a continuing basis, couplant exiting the cavity via the face plate opening and said gap.

Claim 8

The method of ultrasonically inspecting a test piece that comprises the steps of: (a) coupling a transducer to a test piece while providing a cavity therebetween and a gap between the cavity and the test piece; (b) connecting the cavity to a pressurized source for a liquid couplant and to an air exhaust vent; (c) forcing the couplant into the cavity at the bottom of the cavity in a swirling path of flow and maintaining said swirling flow path until the cavity is filled with the couplant; (d) simultaneously with filling the cavity, exhausting air therefrom through said vent; (e) when the cavity is filled, sealing off the air vent while simultaneously adjusting the inflow of liquid couplant into the cavity along its swirling path to a rate just sufficient to replace any couplant leaked from the cavity through the gap, to maintain the cavity in a filled condition while said transducer is coupled to the test piece; (f) terminating the inflow of water at times when the transducer and test piece are not coupled; and (g) when the transducer and test piece are coupled, directing said beams against the test piece through the swirling flow path of said couplant.

Claim 9

The method of ultrasonically inspecting a test piece that comprises the steps of: (a) coupling a transducer to a test piece while providing a cavity therebetween and a gap between the cavity and the test piece; (b) connecting the cavity to a pressurized source for a liquid couplant and to an air exhaust vent; (c) forcing the couplant into the cavity at the bottom of the cavity in a swirling path of flow and maintaining said swirling flow path until the cavity is filled with the couplant; (d) simultaneously with filling the cavity, exhausting air therefrom through said vent; (e) when the cavity is filled, sealing off the air vent while simultaneously adjusting the inflow of liquid couplant into the cavity along its swirling path to a rate just sufficient to replace any couplant leaked from the cavity through the gap, to maintain the cavity in a filled condition while said transducer is coupled to the test piece; (f) terminating the inflow of water at times when the transducer and test piece are not coupled; and (g) when the transducer and test piece are coupled, directing said beams against the test piece through the swirling flow path of said couplant.